重离子碰撞中产生的K介子的末态作用

推广了RVUU模型,计入了K介子的平均场势和K与核子的末态重散射.并用它模拟了每核子1GeV入射能量的两个Ca核碰撞的阈下K⁺产生.讨论了K⁺矢量势和K⁺末态重散射效应对K介子的末态性质的影响.计算结果表明,排斥的矢量势,与K⁺的末态重散射相似,明显地影响了末态K⁺动能谱,导致了实验室系中具有大动量的K⁺产额的增大.然而,排斥的K⁺矢量势的计入可观地减少了K⁺的末态重散射的影响.这说明,为了合理地评价K⁺能谱和角分布,K⁺同核子的这些末态作用都是不能忽略的.

Final-state Interactions of Kaons Produced in Heavy-ion Collisions

We generalize the relativistic Vlasov-Uchling-Uhlenbeck model to include the kaon mean-field potential and the final-state rescatterings of kaons with nucleons,and use it to simulate the subthrcsbold kaon production from the collisions of two Ca nuclci at an incident energy of 1GeV/nucleon. The effects of the vector meanfield potential and the kaon rescattering on the final-state properties of kaons are analyzed. From the calculated results it is found that the effect of repulsive vector potential due to nucleons on the final-state kinetic energy spectrum of kaon is similar to that for the kaon final-state rescattering and leads to an significantly enhanced yield of kaons with large momenta in the laboratory system. However, the effect of the kaon rescattering on its kinetic energy spectrum is reduced considerably by including the repulsive vector potential. This indicates that these final-state interactions of kaons with nucleons are not negligible in order to evaluate reasonably thekaon energy spectrum and angular distribution.